Dual fluid injector assembly



Feb. 24, 1970 a. F. LOEWEN DUAL FLUID INJECTOR ASSEMBLY File d Kay 27,1966 Ama""" N GP lNVENTOR B F LOEWEN B) y a 2 A T TORNEYS United StatesPatent 3,497,324 DUAL FLUID INJECTOR ASSEMBLY Bruno F. Loewen,Brownwood, Tex., assignor to Phillips Petroleum Company, a corporationof Delaware Filed May 27, 1966, Ser. No. 553,475 Int. C1. C!) 57/00 US.Cl. 23259.5 6 Claims ABSTRACT OF THE DISCLOSURE A dual fluid injectorassembly having a plurality of fluid injection conduits positioned inaxial, concentric relationship, the injector being adapted fordisassembly and replacement of the injection conduits while flow ismaintained through at least one of them.

This invention relates to a dual fluid injector assembly. In one aspectthis invention relates to a dual fluid injector assembly which isadapted to be employed in a carbon black furnace. In another aspect thisinvention relates to an improved carbon black furnace provided with saiddual fluid injector assembly.

In the prior art it is known to introduce an annular stream of air orother gas around a tube or pipe through which a hydrocarbon feedstock isbeing introduced into a carbon black furnace. This stream of air orother gas is commonly known as jacket air or jacket gas. One purpose ofsaid jacket air is to reduce carbon deposits around the discharge end ofthe hydrocarbon feedstock introduction tube. Another purpose of saidjacket air or jacket gas stream is to serve as a coolant for thedischarge end of the hydrocarbon feedstock introduction tube.

Difliculties have been encountered with the feedstockjacket airinjection assemblies of the prior art because there is a tendency forthe metal parts exposed to the high heat of the furnace to burn and/orerode away. This is particularly true when for any reason it isnecessary that the injection assembly be exposed to the hightemperatures of the furnace without at least one of the fluids flowingtherethrough. Different types and/or sizes of injector assemblies arefrequently employed in making different types of carbon black and whencharging different types of feedstocks. Thus, the type and/or size ofthe fluid injector assembly is frequently changed. When employinginjector assemblies of the prior art, it is necessary to cut off the airflow at such times of change, and the ends of the jacket air tube andfeedstock tube which extend into the furnace are exposed to the highheat of the furnace. Damage to said tubes frequently occurs during theseperiods when no air is flowing, such as when a fluid injector assemblyis being installed or removed.

I have now discovered that by fabricating the dual fluid injectors asdescribed herein that the above difficulties can be eliminated or atleast mitigated. In the dual fluid injectors of this invention thefeedstock tube-jacket air tube can be removed as a unit while air isflowing through said jacket air tube, thus protecting both of said tubesat all times. This results in a longer life for the injector assemblyand longer periods of satisfactory furnace operation.

An object of this invention is to provide an improved dual fluidinjector. Another object of this invention is to provide an improveddual fluid injector which is particularly adapted to be employed in acarbon black reactor. Another object of this invention is to provide animproved dual fluid injector assembly which can be quickly and easilyinstalled in, or removed from, a carbon black furnace while at least onefluid is flowing through said assembly. Another object of this inventionis to provide an improved dual fluid injector assembly which can bereadily fabricated from commercially available components and which canbe conveniently stored in different sizes for quick change orreplacement. Still another object of this invention is to provide animproved carbon black furnace which is provided with an improved dualfluid injector assembly in accordance with the invention. Other aspects,objects, and advantages of the invention will be apparent to thoseskilled in the art in view of this disclosure.

Thus, according to the invention, there is provided a dual fluidinjector assembly, suitable for a carbon black furnace, comprising: afirst tube; first coupling means attached to one end of said first tube;a first conduit extending from within said one end of said first tubeand forming a first annular space surrounding said first conduit; afirst closure means disposed in and closing said first annular space ata position between said first tube and said first conduit; a secondconduit extending into and through said first tube, and into and throughsaid first conduit from one end thereof to a point adjacent the otherend thereof; a second closure means surrounding said second conduit andclosing said first tube adjacent the other end thereof; and a fluidinlet conduit connect to said first tube.

FIGURE 1 is a view, partly in cross section, of a dual fluid injectorassembly in accordance with the invention, and illustrating saidassembly installed in an inlet passageway to a carbon black furnace.

FIGURE 2 is a view, partly in cross section, of one type of carbon blackfurnace in which the dual fluid injector assembly of the invention canbe employed.

FIGURE 3 is a view, partly in cross section, of another type of carbonblack furnace in which the dual fluid injector assembly of the inventioncan be employed.

FIGURE 4 is a view in cross section of a detail of one modification ofthe dual fluid injector assembly of FIG- URE 1.

Referring now to the drawings, wherein like reference numbers areemployed to refer to like elements, the invention will be more fullyexplained. In FIGURE 1, there is illustrated a dual fluid injectorassembly, designated generally by the reference numeral 10, andillustrated as being installed in an inlet passageway 12 of a carbonblack furnace. Said furnace comprises a heat insulated body 14 having achamber 16 formed therein. The wall of said chamber 16 and said inletpassageway 12 is lined with a more heat-resistant refractory 18. A metalshell or hous ing 20 is provided around the outside of said furnace.

Said dual fluid injector assembly 10 comprises a first tube 22 and asecond tube 24. The downstream end of first tube 22 and the adjacentupstream end of second tube 24 are coupled together by coupling means26, here shown to be a conventional pipe union but which can be anyother suitable coupling means, such as two flanges which can be boltedtogether, with one flange connected to the downstream end of first tube22 and the other connected to the upstream end of second tube 24. Ashere shown, said union comprises a first connector member 28 which canbe secured to the downstream end of first tube 22 by threads, as shown,or any other suitable means as by welding. A second connector member 30is secured to the upstream end of second tube 24 in a like manner. Saidconnector members 28 and 30 seat at face 32 which can be any suitabletype of face providing a fluidtight seating surface. The faces of saidconnector members can be plain, as shown. Or, while not shown in thedrawing, one of said members 28 or 30 can be provided with a recess inthe face thereof and the other member provided with a cooperatingprojection which seats in said recess. Another type of connection whichcan be provided at said face 32 is an O-ring which seats incorresponding grooves provided in the faces of members 28 and 30. Saidmembers 28 and 30 are brought together and maintained together by meansof nut 34,

which engages a boss on member 28 and threads on member 30 in knownmanner.

A first conduit 36 is disposed with its upstream end positioned withinthe downstream end of said first tube 22. Said first conduit extendsthrough said coupling means 26, through said second tube 24, and forms afirst annular space 38 which surrounds said first conduit 36. Thedownstream end of said first conduit extends beyond the downstream endof said second tube 24 as shown. A first annular closure member 40 isdisposed in and closes said first annular space 38 at a position betweensaid first tube 22 and said first conduit 36. In practice, said firstclosure member can comprise an annular washer or like element and ispreferably rigidly connected, as by welding, or by any other suitablemeans, to the outer circumference of said first conduit 36 and to theinner periphery of said first tube 22.

A second conduit 42 extends into and through said first tube 22, throughsaid first conduit 36, and terminates at a point adjacent the end ofsaid first conduit 36. A second annular closure member 44 surrounds saidsecond conduit 42 and closes said first tube 22 at a point adjacent theupstream end thereof. Said second closure member 44 can be any suitablering-like member and is preferably rigidly connected to the outercircumference of said second conduit 42 and the inner periphery of firsttube 22 as by welding, or in any other suitable manner. A fluid inletconduit 46 is connected to said first tube 22 in communication with theinterior thereof at a point downstream from said second closure member44.

Preferably, said first tube 22 and said second tube 24 are ofsubstantially the same inner diameter and are coupled together insubstantial axial alignment as shown in the drawing. Said first conduit36 is preferably disposed substantially concentrically with respect tosaid first tube 22, said coupling means 26, and said second tube 24; andsaid second conduit 42 is preferably disposed substantiallyconcentrically with respect to said first tube 22 and said first conduit36.

A second pipe union 48 is connected on one side thereof to fluid inletconduit 46 and on the other side thereof to an air supply conduit 50 andcouples said two conduits together in known manner. A third pipe union52 is connected on one side thereof to second conduit 42 and on theother side thereof to feedstock conduit 54 and couples said tWo conduitstogether in known manner.

FIGURE 2 illustrates one type of carbon black furnace in which the dualfluid injector of the invention can be employed. Generally speaking, thefurnace of FIGURE 2 comprises a heat-insulated body 14, a first chamber16 having a diameter greater than its length, and a second chamber 17having a length greater than its diameter and positioned downstream fromsaid first chamber. FIGURE 3 illustrates another type furnace in whichthe dual fluid injector assembly of the invention can be employed.

In practice, when operating a carbon black furnace and employing a dualfluid injector of the invention, one fluid, commonly air, is introducedinto the furnace via inlet conduit 46 and second annular space 39. Asecond fluid, the hydrocarbon feedstock, is introduced via secondconduit 42. Said second fluid can be introduced in liquid phase, invapor phase, or in mixed phase. Thus, gaseous hydrocarbons, liquidhydrocarbons, partially vaporized hydrocarbons, or mixtures ofhydrocarbon vapors and hydrocarbon liquids can be introduced as thesecond fluid through conduit 42. The state of said hydrocarbon fluidwill determine the type of opening provided at the downstream end ofconduit 42. When said hydrocarbon fluid is vaporous or substantially so,it is usually preferred that the downstream end of conduit 42 be open asshown in FIGURE 1. When said hydrocarbon fluid is a liquid orsubstantially so, it is preferred that the downstream end of conduit 42be provided with a suitable spray n zzle @11 1! as shown in FIGURE 4.Said spray nozzle can be any suitable type. That shown in FIG- URE 4 isa simple type comprising an orifice plate 60 held in place by unionmember 62. The hydrocarbon fluid and the air can be injected separatelyas indicated by the apparatus of FIGURE 1 or can be mixed. In the lattersituation, it is within the scope of the invention to provide thedownstream end of conduit 42 with any suitable mixing means, such asradially disposed holes, which will inject or direct the hydrocarbonfluid from conduit 42 into the other fluid being introduced throughannular space 39.

Referring to FIGURE 1, the hydrocarbon feedstock fluid from the injectorassembly of the invention enters chamber 16 of the carbon black furnaceand is there surrounded by hot combustion gases. The hydrocarbonfeedstock is converted to carbon black in known manner by the action ofthe heat contained in said combustion gases. The method of obtaining andintroducing said hot combustion gases will depend upon the particulardesign of the furnace being employed, as will be understood by thoseskilled in the art. The carbon black product is recovered from theeflluent from chamber 17 or 16'. These methods are all known to personsskilled in the art.

The dual fluid injector assembly of the invention can be fabricated inany convenient size, depending upon the type of furnace in which it isto be employed. For example, in one embodiment employed with one type offurnace wherein chamber 16 is 37 inches in diameter and 12 inches long,first tube 22 and second tube 24 are made from nominal three-inch pipeand each is about 6 inches long. Union 26 can be a conventional pipeunion and if desired can be provided with hammer lugs for quick openingand closing. First conduit 36 is made from nominal two-inch pipe andsecond conduit 42 is made from nominal one-inch pipe. In one embodiment,first conduit 36 has a length of about 35 inches. In another embodiment,said first conduit 36 has a length of about 31 inches. The length ofsecond conduit 42 will usually be such that the downstream end thereofwill be positioned about /2 to 1 inch within the downstream end of firstconduit 36. However, it is within the scope of the invention for thedownstream end of said second conduit to be flush with or extendslightly beyond the downstream end of said first conduit. The abovedimensions are given by way of example only and are not to be consideredlimiting on the invention.

Referring again to FIGURE 1, in a preferred embodiment of the invention,first coupling member 28, first tube 22, first conduit 36, secondconduit 42, and fluid inlet conduit 46, together with closure members 40and 44, form a first unitary subassembly. Similarly, second tube 24 andsecond connectnig member 30 form a second unitary subassembly. In thepractice of this presently preferred embodiment of the invention, saidsecond sub assembly is connected at the downstream end of second tube 24to the wall 20 of the furnace in any suitable manner, as by welding.Said two subassemblies are connected and maintained together by means ofnut 34 as previously described.

In practice, assuming the furnace is hot and operating, and it isdesired to change the fluid inlet assembly, e.g., change from an openend to a spray nozzle on the end of conduit 42, the furnace will bemaintained hot during such a change for obvious economic reasons. Tomake the change, flow of the hydrocarbon feedstock is discontinued andunion 52 parted. Nut 34 is then loosened and said first subassembly isremoved, thus withdrawing first concuit 36 and second conduit 42 fromthe furnace while air is flowing through fluid inlet conduit 46, tube22, and annular space 39 to protect the downstream ends of said conduits36 and 42 from the heat of the furnace. A new first subassembly of thetype desired is then connected to air conduit 50 at union 48, the airsupply is started, the new first subassembly is placed in position asshown, and the two subassemblies hooked together at union 26. In

this manner an old assembly can be removed and a new assembly installedwith air flowing through first tube 22 and annular space 39 to protectthe downstream ends of the assembly from the heat of the furnace. Airconduit 50 is preferably flexible to facilitate making said change.Similarly, feedstock conduit 54 can also be flexible if desired.

While certain embodiments of the invention have been described forillustrative purposes, the invention obviously is not limited thereto.Various other modifications will be apparent to those skilled in the artin view of this disclosure. Such modifications are within the spirit andscope of the invention.

I claim:

1. A dual fluid injector assembly comprising:

(a) a first tube;

(b) a first coupling means attached to one end of said (c) a second tubeattached to said first coupling means;

(d) a first conduit of substantially uniform internal diameter extendingfrom Within said first tube into said second tube to form a firstannular space surrounding said first conduit;

(e) a first closure means closing said first annular space at a positionbetween said first tube and said first conduit;

(f) a second conduit extending into and through said first conduit toform an annulus of substantially uniform diameter between said secondconduit and said first conduit;

(g) a second closure means between said second conduit and said firsttube; and

(h) a fluid inlet conduit in open communication with said first tube.

2. A dual fluid injector assembly in accordance with claim 1, wherein:said first tube and said second tube each has a downstream end and anupstream end; said two coupling means comprise a pipe union connectingsaid downstream end of said first tube and said upstream end of saidsecond tube together; said first conduit and said second conduit eachhas an upstream end and a downstream end; the upstream end of said firstconduit is positioned within the downstream end portion of said firsttube and the downstream end portion of said first conduit extends beyondthe downstream end of said second tube; said first closure meanscomprises a first annular member rigidly connected to the outercircumference of said first conduit and to the inner periphery of saidfirst tube; the upstream end of said second conduit extends beyond theupstream end of said first tube; the downstream end of said secondconduit terminates adjacent the downstream end of said first conduit;and said second closure means comprises a second annular member rigidlyconnected to the outer circumference of said second conduit and theinner periphery of said first tube at the upstream end thereof.

3. A dual fluid injector assembly according to claim 2, wherein a secondpipe union is connected to the other end of said fluid inlet conduit,and a third pipe union is connected to the upstream end of said secondconduit.

4. A carbon black furnace comprising, in combination: a heat-insulatedbody; a generally cylindrical chamber formed in said body; a passagewaycommunicating between the interior of said chamber and the exterior ofsaid body; and a dual fluid injector assembly in accordance with claim Imounted on said body in communication with said passageway and theinterior of said chamber.

5. A carbon black furnace comprising, in combination: a heat-insulatedbody; a chamber having a diameter greater than its length formed withinsaid body; a passageway communicating axially with the interior of saidchamber and the exterior of said body; and a dual fluid injectorassembly in accordance wtih claim 2 mounted on the exterior of said bodywith the downstream end of said second tube disposed around the outerend of said passageway and the downstream end of said first conduitextending into said passageway.

6. A carbon black furnace comprising, in combination: a heat-insulatedbody; a chamber having a length greater than its diameter formed withinsaid body; a passageway communicating axially with the interior of saidchamber and the exterior of said body; and a dual fluid injectorassembly in accordance with claim 2 mounted on the exterior of said bodywith the downstream end of said second tube disposed around the outerend of said passageway and the downstream end of said first conduitextending into said passageway.

References Cited UNITED STATES PATENTS 891,349 6/1908 Loder 431-1763,087,796 4/1963 Latham et al 23259.5 2,518,025 8/1950 Knight 431187JAMES H. TAYMAN, JR., Primary Examiner US. Cl. X.R.

